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CVE-2026-43024 Linux CVE debrief

A vulnerability has been identified in the Linux kernel, specifically in the netfilter component of nf_tables. This vulnerability involves the rejection of immediate NF_QUEUE verdicts. The nf_tables is a packet filtering framework that provides a more flexible and efficient way to filter packets than the traditional iptables. NF_QUEUE is a verdict that queues the packet for user-space processing. However, immediate NF_QUEUE verdicts are not used by userspace nft tools and can be problematic. To address this, the Linux kernel has introduced a fix to reject immediate NF_QUEUE verdicts globally, including for the arp family which does not provide queue support but could still be affected.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-28
Advisory published
2026-07-14
Advisory updated
2026-07-28

Who should care

System administrators and users of Linux operating systems should be aware of this vulnerability, especially those who manage or use systems that could be affected by the exploitation of this issue. This includes but is not limited to servers, workstations, and IoT devices running vulnerable versions of the Linux kernel.

Technical summary

The vulnerability CVE-2026-43024 is related to the netfilter component of the Linux kernel, specifically within nf_tables. The issue revolves around the handling of immediate NF_QUEUE verdicts, which are not typically used by userspace nft tools. The Linux kernel has implemented a fix to globally reject such immediate verdicts to mitigate potential security risks. This change affects various versions of the Linux kernel, including but not limited to versions 4.19.307, 5.4.269, 5.10.210, 5.15.149, 6.1.76, 6.6.15, 6.7.3, and 6.8.1. Users and administrators should ensure their systems are updated with the latest kernel patches to prevent exploitation.

Defensive priority

Medium

Recommended defensive actions

  • Apply kernel updates to ensure systems are running with the latest security patches.
  • Review system configurations and ensure that nf_tables is properly configured.
  • Monitor system logs for any suspicious activity related to nf_tables and NF_QUEUE.
  • Consider implementing additional security measures such as firewall rules and intrusion detection systems.
  • Perform a thorough review of system configurations and network architecture to identify potential vulnerabilities.
  • Implement asset inventory management to track and manage Linux systems.
  • Establish a process for tracking and addressing exceptions during remediation.

Evidence notes

The CVE record was published on 2026-05-01T15:16:46.760Z and was last modified on 2026-07-14T13:18:51.963Z. The NVD entry is currently Modified. Multiple patches have been provided by the Linux kernel maintainers to address this vulnerability.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-43024 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-43024

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-43024 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-43024

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/17dc5d5a935c771338430cbc156a16a51cfd31e8

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/2f7f825a548be55420f0f5f716f6c27b9d312d3f

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/42a47f4b1b7695026ab9bc1bb35d4622b0835c95

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/4b12a3cc3f075e750cc3c5e693fd25fb400af4a2

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/68390437a998c3f2c57212b413abef5e6d657d88

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/da107398cbd4bbdb6bffecb2ce86d5c9384f4cec

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f140593901724cfbd16597c3a4fcb24a58ae44b0

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.